The existence of infectious diseases such as AIDS and Hepatitis has highlighted the danger to which medical personnel may be exposed when treating patients by means of catheter devices where a sharp needle point is used to pierce the skin of a patient. Medical personnel have been infected by physical contact with or accidental prick by an infected needle (needle-stick).
In order to protect medical personnel against inadvertent needle-stick a number of solutions have been developed whereby a protective means incorporated within the catheter prevents physical contact with the needle after use and hence against inadvertent needle-stick.
A known device for protecting a needle both before and after use is described in European Patent Publication No. 0599564, in which a needle is arranged within a housing and is displaceable between a retracted position and a second extended position. Means is provided for displacing the needle between said first and second positions. A sealing means for sealing the initially open distal end of the housing is connected to the displacing means, at least initially. The sealing means during displacement of the needle from said first retracted position to said second position, is moved in the direction towards the open distal end of the housing to a sealing position and is then fixed in said sealing position substantially sealing the interior of the housing.
The structure described in European Patent Publication 0599564 although effective to prevent inadvertent needle-stick is complicated and relatively expensive to manufacture. Furthermore, th e structure does not give any clear visible sign to show the user that the needle is locked in the protected position.